Electronic circuits sometimes share wires to reduce pin count, failure modes, and cost. Some electronic circuits share a common ground terminal for two or more signals traveling from one portion of the circuit to another.
In one particular example, mobile computing devices operating according to the CEA-936A universal serial bus (USB) standard can share a ground terminal in certain configurations. The CEA-936A standard supports analog accessories such as telephony and multimedia headsets. Audio signals communicated between the mobile computing device and accessories share a ground terminal.